The present study was designed to explore the relationship between psychological stress and esophageal motility disorders. Nineteen non-cardiac chest pain patients (10 with the nutcracker esophagus and nine with normal baseline manometry) and 20 healthy control subjects were administered two acute stressors: intermittent bursts of white noise and difficult cognitive problems. The results indicated that the esophageal contraction amplitudes and levels of anxiety-related behaviors of non-cardiac chest pain patients and control subjects were significantly greater during the stressors than during baseline periods. All patients demonstrated significantly greater (P less than 0.01) increases in contraction amplitude and anxiety-related behavior during cognitive problems than during the noise stressor. The nutcracker esophagus patients showed a greater increase in contraction amplitude during the problems (23.50 +/- 9.42 mm Hg, X +/- SE) than control subjects (P less than 0.01), while the amplitude changes of chest pain patients with normal baseline manometry were not significantly greater than that of control subjects (9.00 +/- 1.91 mm Hg). The present results identified an increase in contraction amplitude as the primary esophageal response to stress. The possible interaction of esophageal contraction abnormalities, psychological stress, and the perception of chest pain is discussed.